The present invention is concerned with an apparatus for manufacturing a so-called consecutive-type reinforced hose, and more particularly, to an apparatus for manufacturing a reinforced hose wherein: a torpedo is formed to protrude from a top end of an inner die of a inner tube extruder; an outer tube extruder has its material efflux port which is composed by an intermediate die and an outer die in such a way that it is disposed in the vicinity of the inner die but outside the outer periphery of the torpedo; and a reinforcing layer-forming device, capable of implanting reinforcing threads led out through a gap formed between the intermediate die and the inner die into the inner tube immediately after the extrusion has been performed, is so disposed as to be concentric with a cylinder of the inner tube extruder.
The above-described apparatus for manufacturing the reinforced hose has already been filed for patent by the applicant of the present application and hence the contents thereof have become broadly known (See Japanese Patent Publication No. 50132/1985, which is believed to be equivalent to the U.S. Patent of Mitsui et al, U.S. Pat. No. 4,472,126, issued Sept. 18, 1984).
Referring now to FIG. 1, there is sectionally depicted a reinforced hose manufacturing apparatus 1.
A torpedo 7 is formed in such a manner that it projects from the tip end of an inner die 5 of an inner tube extruder 3. An outer tube extruder 11 is arranged such that a material efflux port 17 constituted by an intermediate die 13 and an outer die 15 is disposed in close proximity to the inner die 5 but outside the outer periphery of the torpedo 7. A spiral device 21 is placed so that reinforcing threads F1, F2 led out through a gap between the intermediate die 13 and the inner die 5 can be implanted into the inner tube immediately after the extrusion has been effected.
In the inner tube extruder 3, the torpedo 7 is attached to a head 6 secured to the tip end of a cylinder 4, and the inner die 5 is fitted to the head 6. In the outer tube extruder 11, the intermediate die 13 and the outer die 15 are respectively mounted to the head 6 with the help of die holders 18, 19.
A reinforced hose A (for instance, a fuel hose suited to an automobile) manufactured by the thus-constructed manufacturing apparatus 1, as illustrated in FIG. 2, assumes a trilaminar structure, i.e., an inner tube B (nitrile rubber; NBR), a reinforcing layer C and an outer tube D (epichlorohydrin rubber; CO).
As for the fuel hose, there is recently a demand for the improvement in property to resist its deterioration by gasoline and for making the inner tube B polychromatic (for example, an NBR layer, a hyperon and a CSM layer are laminated from the side of its inside diameter) in terms of enhancing the bonding properties with respect to the outer tube D.
Such a polychromatic inner tube B is, in general molded by use of a polychromatic extruder 23 depicted in FIG. 3. The polychromatic extruder 23 includes a first extruder 25 serving to mold a first layer B.sub.1 (counted from the side of the inside diameter) of the inner tube B; and this first extruder 25 is equipped with a cylinder 26 disposed at an angle of 45.degree. to the extended axial line (superposed on a mandrel 45) of the head 43. A second extruder 35 performing a function to mold a second layer B.sub.2 is provided with its cylinder 36 disposed at an angle of 60.degree. to the extended axial line of the head 43.
Such is the arrangement of the first extruder 25 that the cylinder, a feed roller 27 and a speed reducer 29 are coaxially placed; and a motor provided in parallel with these components is connected through a driving belt 31 to the speed reducer 29.
The second extruder 35 is constituted in such a way that the cylinder 36, a feed roller 37 and a power-conveying unit 38 are coaxially disposed; and a motor 40 is placed in parallel with the power-conveying unit 39. The speed reducer 39 is connected through a driving belt 41 to the power-conveying unit 38.
The thus-constituted polychromatic extruder 23 can not, however, be applied to the reinforced hose manufacturing apparatus 1 having such a configuration as illustrated in FIG. 1. The reason for this is that the cylinders 26, 36 of the individual extruders 25, 35 intersect each other and are secured to the head 43, thereby interfering with the spiral device 21.